Optical comparison hemoglobinometer having a reflector supporting transverse partition



Sept. 20, 1949. M. G. BROWN ET AL OPTICAL COMPARISON HEMOGLOBINOMETERHAVING A REFLECTOR SUPPORTING TRANSVERSE PARTITION 3 Sheets-Sheet lFiled Dec. 26, 1945 NON G n w e .0 o T EM T f, A G. NF, M M MH Y B sept.2o, 1949.i

M. G. BROWN ETAL OPTICA-L COMPARISON HEMOGLOBINOMETER HAVING A REFLECTORSUPPORTING TRANSVERSE PARTITION Filed Dec. 26, 1945 5 'Sheets-Sheet 2 InJ IN VEN TOR.

BY-W l I Sept 20, 1949- M. G. BROWN ETAL OPTICAL COMPARISONHEMOGLOB'INOMETER HAVING A, REFLECTOR SUPPORTING TRSVERSE PARTITION medDec ze 1945 INVENTOR. MOPoE/v G. 52o w/V H Patented Sept. 20, 1949UNITED STATES PATENT 'OFFICE 2,482,650? v Y t GPTICAL COMPARISONHEMOGLOBINOM- ETER HAVING A REFLECTOR SUPPORT-T ING TRANSVERSE PARTTTIONl Morden G. Brown, Williamsville, and: Harry. F.

Lundberg, Bulalo, N. Y., assignors to American Optical Company,SouthbridgafMass., a ,volun- 1 tary association of Massachusetts IApplication December 26, 1945 Serial No. 637,230

This invention relates to hemoglobinometers,

and more particularly to such an instrument.

which is compact and convenient for use by a physician in his oliice andwhich is also readily portable so that it may be easily carried by thephysician in his bag and used anywhere when desired for rapidly andaccurately examining the hemoglobin content or concentration of apatients blood. This application is an improvement over co-pendingapplication Serial No. 440,476, filed April 25, 1942, which is issuedMarch 12, 1946, as Patent No. 2,396,260.

In the hemoglobinometer shown and described' in said earlier filedapplication the out-er casing is divided generally longitudinally toform two separable sections. The lower of these sections encloses a pairof dry cell batteries and between the batteries are a light bulb and aconical reilector. In transverse alignment with the bulb is a manuallyoperable switch for controlling the operation of the bulb. rThis switchis purposely located in such a position so as to be convenient foroperation by the physician while sightingv through the eyepiece andoperating the slide of the instrument. The upper of said separablesections of the device contains a partition enclosing and supporting aspecimen holder and an adjustable comparison member and adjacentthereto, in transverse alignment with the bulb in said lower section, isa prism reilector arranged to reilect areas'of lightfrom portions of thespecimen holder and the adjustable comparison member for observationthrough sighting means in an end wall of said upper section. Alsocarried on the partition are a diifusing plate and a color lter whichproject outwardly therefrom and toward the light bulb and the reector.Accordingly, the amount of space available transversely of the casingfor Vpositioning the bulb and reflector and for allowing properoperation of the manual switch was materially limited since thetransverse dimension of the casing could not be increased without makingthe instrument less convenient to handle and use.

Applicant has foundv that improved results can be obtained by placingthe'color filter adjacent the sighting means near an end wall of saidsecond section, instead of adjacent the bulb, and, accordingly,providing more room for the bulb improved reflector. Such constructionalso affords more space for movement of the manual switch alignedtherewith. The positioning of the color filter or light-absorbing memberadjacent the eyepiece of the instrument also gives better results sincethe light-abSQrbng properties of the 1.6 claims. (c1. l:s- 14) lter aremore uniform. This is because the light from` both. .areas underobservation passes through substantially .the same part of the filter,instead of widely separated parts as formerly,

j and thus there is les'schance for` variations in density in the filteraiecting the matching of the two areas.. .Also av lter of smaller sizecan be employed thus reducingthe weight and costV of the instrument.Furthermore, the filter which is .generally formed of a gelatinousmaterial is in :its new location completely enclosed and thus protectedfromV scratchesor injury when the instrument is opened for replacementof the bulb or batteries. Since the partition is formed of metal itValso forms an -improved means for engagement by the catches holding thecasing sections together, avoiding the danger of breaking the edge ofthe molded plastic section which in the former construction was engagedby the catches. i

The device of said earlier filed application was arranged with itsreflecting member or prism imbedded in a part ofthe upper. section ofthe casing and held in place jointly by said section and parts carriedby the removable partition enclosing the section. Applicant has Vfoundthat an improved` constructionmay be had by providing means carriedentirely and directly by the partition for supporting the prism and areleasable spring member therefor, so'that these parts may bereadily'and correctly assembled and tested, if desired, before they arepositioned within the upper casing section.` l

Improvements Ain construction over the instrument of said earlierapplication have also been obtained by providing'an integral framemember which is formed so as to provide a support for the prismreilector and said releasable spring, and provide a sighting channelhaving nonreflecting surfaces formed therein. Said frame member is alsoformed to provide, in cooperation with said partition, va'chamber forreceiving the specimen holder and adjacent thereto a guideway for theadjustable comparison member. The construction and arrangement of theinstrument with these several parts positioned upon the partition beforethey are inserted and secured in said casing section .provides aconvenient and accurate mann-er and vmeans for positioning and initiallyoptically aligning these parts and produces a stronger more rigidconstruction. Spring means is provided in Vthe instrumentfori-releasably holding the specimen holder in its operative position insaid chamber and other spring means is provid-ed for frictionallyholding said adjustable comparison member in its adjusted position.

A more complete understanding of the invention may be had from aconsideration of the detailed specication which follows taken inconjunction -With the1 aocompanyhi'gf.dnawings;-. ine 5 which:

Fig. 1 is a side elevational view of the instrument of the invention asviewed from one side: thereof;

Fig. 2 is a similar view but"sliowing-:tri'e'instru-1 l0v ment as viewedfrom the otlaensdefthereoigl Fig. 3 is a somewhat enlarged transversesec--4 tional view taken substantially'omilinea-s-S-off Fig. 4;

Fig. 4 is a side View of theistrument-isimiiar w offv theprismreflectoiirandresili'ei'it retaining 30.

means= therefor-3' 'and Referring 'to ith" -draavin'gsdeter-111and:pai.iVv ticu'larlsr Fig'sll-, thedeviceoninstrument'shown35 theifeiiif comprises-lacasingf'ozfihousirrg generallyindicated bythefnumeralancla fo'rm'edczof `tvvoif separable sectinsi:Wland-Iihavingintertting; abutting 'edges-1 Iand l llS-respectivelyf. These? sectionsmay be detachably secured together-..2'by fioresi-lient"elipse-01"'catchesfvll:securedtfrthecrst or lowerI sectionflrzbyfsuitbiesmeans ssuchaxas screws fill-1i The -secti'onsfl it-anusIe3arefprereliablyV madef of" molded?palestreY materiali but: be formedor" any* other sintabieemateriai.; desired;` 45 TheowersectiorilZisf-prnviieduwitliia pair ois longitudinallyispaced'ibatterieseland F9;ofr'the conventional *diiyfi'cell 'ashli'gktivaretigandipositionedbetweenf tlie batteries: as lightso'ree'2B"comprisiiigrfafbiiibZEanuanfiaspherifcvreector 50 24 fwh'i'ch willibe'f laterfd'escribeds more-fully.' A manually operablf-.pushh buttorr263i is# arranged in transverse alignment witlintireffbuib: ozrthafaswitch or 'el'ectfiealf"corriaci?irrerrllb'enzloperated tl'fereby I'may4 be'A movredii into?y Contact" with?v the 55 central"terminallfofithei bhlbi- Thel sections#1 I-Z andi- I Sifmayfaflso :beiAprovided w-itfr aligningmeansf comprisnrgfv ai pair: ofi'up= standinglugs 3Ui'onf'eacheoiI-E theC opposite side edges oft one" ofArsaid-'lfsectionse and-'ff eaclfrf pair 69 adaptedto' engagev afcomplementary-'recess 32 in the-"otl'erof"said-lsectionsftor'aidirrg..in cen*- teringf thetvvef-sectionsi asthey' 'arefb'rought to' getherfandf into closedfrelatfem Each?l pair-pflugsV 3ll'iis'V` spaced? iiiWard-l'offthe router; surface 65oiitslsupportinfga section 1' sowastof engage' in itsrecess=-32`5`inward1yoffte outerfs'rdeiwany surfaceor-"theLsectiorr'containingJtIemeCeSS: Projections 35' 'may be' formedonf one'f of? th'el sections 'and slots 35i-mawbe=provicieemh tleotli`erotfthese 70 sections to' servefas=meansf1frf exantly'positi'on- Ain-gvthe sections lxrgiterdinal-ly*relative to" each other';

The upper sectionY If` offrire-ceasing' isf provided Withfinteg-raliupstandngf'lss'or supportsrs ad'.- 75

jacent opposite ends thereof for receiving the screws 40 serving tosecure a partition 42 in place in this section and the partition e2 isprovided adjacent its opposite ends with apertures M arrangedetoreeeive-.the bentxupstanding ends i5 offitlie spring clips.- l6andireleasablyretain the sections l2 and I3 in closed position. Thepartition G2 is also provided with a central aperture 43 over which maybe placed a diffusing plate 45""whichfmayb'e secured in place by aframing memberA-T-tand-screws 48.

Tfie bulb" 22, referred to above, is positioned suiicientlybelowetheediiusing plate 45 to give structurallcleavan'c .between theparts when the sectionsfl2`iandl3'are clamped together, and inorder"'^t^obtain substantially uniform illumination over the exposed.central portion of this plate the reector 24 is made somewhat largerthan theconical rellector of the instrument of said earlier filedapplication and is aspherically shapedfz. Tlie arelect'onl Miseso:shapedliorA curved inticrosszsection that the lightreflectedethereby;

ontoithezfpiate 2&5? diminishes; inn intensity from*therouterrportionsfot the:diifusingziplateaftowara th'efcenterinverselyiy asatheadirectf-lightx: from-ther bulb"var`res. onithenplateiromrthe center toward-` th'eif outerrportions:thereon Thus@together1 the. bulb andgrefiector"providersubstantialljr,uniform1yilluminationiover iailspartswof :thefplatei letachably; secured@ .upon;ithefpartition ll2.` by; sadcscrewsi 418i is aa unitary i orfrintegral.frame: member 5m? preferably, formedsasiadiecasting; or? itymi'ght be:oir' molded: 1. plastica, and shaped tof'provide La. pair .'oflaterallyextendinggvertical: fian'gesf 5'2 constituting; sidewalls:4 for aAcentral chamber eedisposedgias best seennby.'1ig.s:-` Biancl. gfatron'eside of"the"longitudinaiovertical central planer-oft the: instrumentarIn= the chamber 54 may` bezpositi'onedf.fasspecimenuholder .f orcarrier; 55Iiwhosefirinermost. positioneisrlimitedi y.by a 'pai-roi'frintegral: steps 53.1 rllhe :fitamef member@ 50 isalsoizshapedstocprovide finzi-.conjunction iwith" the partition 42.-*fanelongatedlongitudinailydisposed guidevvajr 56 locatedcatthe oppositesidefofzsaidi centratvertical planer-landwirt thefguideway i 5e:isiipositioned: am adjustable comparisommember. 511.1. TheShoi'drlieandzthe comparison :member 51' :'will.. :be hereinafternroreiui'lyf'describedf.. Thel member. '5 T r'is transparentertranslucent-andmay beeiniz the* form.:l or? aa uniformly? tapered."ywedge member.x or a-` n'remb'eri havingtuniforrnlyvaryingdensityfrthroughout its zlengtlfiesosthaigin i either case; n af:member` willi bev providedrlhaving "known, light-absorbingfqualitiesAiplateifids :clamped betweenthe` artitionrez :arrdthe unitarifram'ememberifbyf th'ef screwsfll and1thisf plate has af ilangef ETI-fextending downwardlyadjacent" arr opening" 632provided?fbetvveenzthesectionsV l2 fand I31fo'r reception' of fthefholder 5.5:. Spring; arms `(i'are formed on plate 59fand!arrangeditofextend into ith'e chamber; 5N" at?l opposite-si'des:off'tthe' aperture' 43? and'serve` to h'oldrthe'.L carrier? 55releasably inf position .1in thef instrument ian-d1un' against the framememberfll The framel lmemb'er `or 'castingvffS' is Yalso. provided withay horizontal portion EBfspace'df. above andl generally parallel 'to fthet partition: 42 and tiff-is portion serves to suppor-:tvlatera'l-ly'spaced integral'upstandirig flangesf 6"havi'g bearings `62fformed1therein-frreceiving endif' portions 64 ofawspring- 66 adapted;wherrfirr'-operative` posi'- ti'on; to'yieltlablyretaiir'afprism1l58finposi-y tion against' l'a'eari'ng'l areas-13-f ande" a Vrecess'Iffiformed'in' the upper sur-face fof fsaidfliorizontal portion-:58imin'ed-iatcelyfvalavovelapairr or apertures e .51j e |2. An integralrib Iis formed centrally on the frame member 50 and closely lits alongitudinal slot or-recess II formed in the bottom of the prism 68.Integral arms 'I4 Iare also provided on the flanges 60 at opposite sidesof the spring 66 and have finger portions 'I6 engaging over resilientprongs `18 bent vupwardly and rearwardly from the body portion of thespring 66 for yield- Iably retaining the spring in said operativeposition. The details of construction of the spring and itsengagementwith the bi-prism 68 are best shown by Fig. 10 wherein it willbe seen that the forward portion of said spring is provided withbifurcated arms 80 engaging laterally spaced portions of fthe prism atpoints on the sloping rear surface thereof at such locations that thelines of force of the spring pressure will pass through the forwardprism supporting areas 8| or between these areas and rear prismsupporting lareas 83. Small ribs 82 may be provided at opposite sides ofthe prism 68 for aiding in centering the prism as it is slipped intoplace in the optical system of the device. v

The integral frame member or casting 50 is also provided with anelongated forward portion 84 whichis formed in the shape of a channel,see Fig. 7, having a bottom 86 extending outwardly and slightly upwardlyfrom the center of the channel and vertical side Wall portions 88. Theseportions 86 and 88 are provided with a series of'inwardly projecting.ribs 90 which taper inwardly and thereby form a non-reflecting innersurface throughout the length of said channel. A cooperatingnon-reilectingwall portion Yis formed upon the inner surface of theupper molded casing section I3 by a series of transversely archedprojections ,92 likewise ltapering inwardly and tting into recesses 94in the upper side wall portions 88 between the ribs 90, thereby forminga substantially enclosed sighting chamber 96 'havingwalls which reect nolight toward sighting means |02 in the end Wall of the section I3.

The sighting chamber 96 has 4an end wall portion 98 formed integrallyupon the member 50 and provided with ian aperture through which lightprojecetd by the bulb 22 and passing through the .diffusing plate 45,aperture 43, the specimen holder 55 and the comparison member 51 andthrough `apertures 'I2 and reflected by the prism 68 may tr-avel toreach the color lilter ||0 and the sighting means |02 in the end wall ofsection I3. The color lter isformed of glass, plastic or gelatinousmaterial which is adapted'to transmit light of only a predetermined-character, that is light of only a certain .predetermined portion oftherspectrum. I'he sighting means |02 is threaded into a sight opening|04 and comprises a tubular portion |06 containing la lens element |08and the-color lter or filtering member I0 positioned adjacent anapertured ydiaphragm II2. It will be obvious that light transmittedthrough the specimen holder 55 and light transmitted through vthe`adjustable comparison member 5'I will 'be reflected by the aaeaesolsame. in an engaging position for positioning inl chamber 54 of thedevice. YThe upper and lower surfaces of the plate |20 are accuratelyformed so as to be parallel and the plate |22 has its lower sur-face andits spaced upper side rails |23 likewise in parallel relation while anintermediate part of the plate |22 is provided with grooves |24 forforming specimen-receiving vareas |26 which are arranged to lie slightlybelow the plane of the side rails |23 so as to form a space between eachof the areas |26 and the bottom of the cover plate |20 positionedthereover, said space being of predetermined thickness for a purpose tobe hereinafter described.

The adjustable comparison member 51 may be cemented or otherwise securedalong the surfaces |3I to an elongated slide or carrier |30 which isarranged to fit within the guideway 56 and rest at |32 upon the uppersurface of the partition 42 so that it may be moved therealong when thedevice is in operation. Spaced lugs |34 are also provided on the upperpart of the carrier |30 and engage atV |36 an outer side wall portionof' the frame member 50. An elongated spring |38 has its opposite endspositioned in recesses in the carrier |30 and its central portion bearsagainsty the inner surface of an upstanding flange |40 formed integrallyalong one side of the partition 42. An operating arm |42, extendinglaterally over the upper edge of the fiange |40 and then downwardly to aposition opposite an elongated slot |44 formed in the casing betweenadjacent edge portions of the sections I2 and I3, has sliding engagementwith the outer surface of the flange |40 as indicated at |46, and thisarm |42, together with the bearing surfaces |32, |36 and spring |38,serves to yieldably and frctionally maintain the carrier in an adjustedposition and allows the carrier to be moved longitudinally to positionvarious portions of the comparison member 51 opposite the specimenholder 55 in the chamber 54. A finger portion |48 is formed on the arm|42 and projects through the slot |44 to serve as a handle when theslide is to be adjusted, said finger being provided centrally thereofwith a mark or groove |50 to serve as an indication of the position ofthe slide relative to a scale or scales on the outside of the casing |I.By providing a scale |52 or avset of scales |53 adjacent the slot |44,an indication of the hemoglobin concentration .of the 'blood may beobserved. v

Different methods of use of the device of the invention may be employed.For example, one method may be performed in the following way: A drop ofblood extracted from a patients fingertip or ear lobe may be placed uponthearea |26 of the plate |22 and stirred by a stick or the like having aminute amount of hemolytic agent carried on the end thereof to convertthe blood specimen into a solution wherein the red pigment or hemoglobinof the blood is substantially evenly distributed throughout thespecimen. The cover plate |20 is then positioned thereover to spread thespecimen and restrict same to a layer of predetermined thickness. Theholder 55 may then be inserted into the chamber 54 of the instrumentthrough aperture 63 and inspected. When the comparison member 51 hasbeen moved longitudinally to a position togive equal lightabsorption tothat of the specimen being examined a reading may be taken on one of thescales |53, depending upon the patient being examined andthe particularstandard being used by the operator or physician, to indicate thehcmoglobiniconccntrationcf-the Specimen.. ThisImethodzandltheaoparatusicmplcrcdthcrewithisf. described in, greater.detail and. Aclaimed in VY@of pending-application No., 627,873, iiledvNovember 1.0,;1945 1 Y A Another; methodofl use of 4theginstrunient.would empleary ai specimen?. of- Y, untreated Whole blood which; isplaced ,in the holder-I 55 .Y and. .inspectedandcomparedcin the-finstrun'ient Without being.. hemolyted;,- Undersuch-a conditionareading.. might ber-taken on -thefscalef |52. tol indicate the,vhemoglobin; concentration.L SuchY use o; Lthe in strumentobviouslifmight be -perfornied-Y- more` rapidly but would not give asaccurate@results since tl1e,` hemoglobina, thereofA would be= conned in=thexindividual cells-separatedby clear plasma. andgthus the .trueVconcentration thereoie Y would not. be;4 directlyreflected:l inizthelight-absorbing.- properties ofi-the specimen as `a whole.

Throughout thefspecification the two separable partslof; thecasingtll-havelbeen referred .to as the; lower section andthe Yuppersection. It isfhere'pointed out, that` the terms have been used.asfavmatter-of convenience and that theA instrument mayL as. readilyVbe used with either section; upwardly; orv may`y be used equally Wellwit-h -thasections disposed side by side, Accorde inglyuch ,terms-shouldnot limit the invention but-V be --considered lonlyf` as descriptive.,

Having; deseribedjthe invention, we claim:

la portablerdevice of` the Ycharacter `described comprising-anelongatedcasi-ng, said casing being divided e;erlerallyg-` longitudinally thereofto forni rstiandgsecond.;sections; battery means and a light source-insaid iirst sectiorn a removable partitionrpcarried by Saidsecondsection'and having an aperture lfor-ined-tl'1erein an integraltrame member-.supportedbysaid partition` and arranged toforni:therewithl anelongated guideway and-a chamber-adjacent@saidaperture, an adjustable comparison member-l arrangedin said guidewayandra removable specimenholder positioned in' said chamber,ai,.,reflectoi:, means irniegral1 withsaid lframeriflelrnber forsupporting'and position-` ing-y said reiector. i in optical alignment:With adjacent portions of sanidad-instable member and said holder,andzsightingzmeansin an end Wall oi saidf, casi-,r-1g; orviewingr lightfrom said.- adjacent portions:A and reilected 'by said relector whenilluminated-ibyfsaid.-lightsource. y

2; Aiportablefdevice of .thefcharacter described comprising an elongatedcasing, said casingvbein-g divided generally` longitudinally thereofv toform rst and-secondsections,V battery means and a lighlifsourceinsaidi'lrst section, a removable partition carriedbysaid-*secondsection and` having an aperture formed therein, a unitaryframe membersuppprtedgblsaid':partition and 'arranged to formvtherewithfanelongated guideway and a chamber-adjacent .said aperture, anadjustablecomparison member arranged in said guideway anda removable specimenholder positioned in said chamber, areflector; means formed as anintegral part of saidframe member orsupportmaand rpsitiooifneigsoid,rcflcctorfinf optical aliene meritzwitlir adjacent portionsofsaidadjustable mem-loerand, saidholder, releasable `means carried by:said-frame;` member for yieldablyhold-ing sai-dreectorfin itsoperative'position, and sighting mea-lis in anend wall of said casingfor viewing lightfromsaid adjacent portions andreflected bysaidreflector-When illuminated by said lightgsource..

3.. Aportable deviceV o f ,thecharacter described comprisinganelongatedA casing, said casing being anapertureiormcdiloercin.,.

` bcr supported. basal forni. therewith.. an-.. elongated.-. euideway.,and.. a chamber.. adiacentgsaid apertulzcnan ,adjustable divided.eolierollini1omitiicliricllr.thcrcoiidform1 list-andnsefmnd,.fscctionoLbattery moans. and

light souoccinlsaidrst' section, a'rernovablo par.-vtiti,oncarried.Jorgsaisi secc Section. and4 .having partitiooand,arranged to comparison-.member arranged in...sai.d.guidewarandaremorablespccimen holder.. positionedfin said.,-chdml-0cr.,Yayrollectcn-moonsiormod es an..

integral...part..ofadramemcmbcr for support-r ins; and.pcstioninaseidreflcctor in. Aoptical align:- mcnt with..adiaocntanorticns.,,ofiL said .adjustable .Y member. and 'SoidhclgdcnASighting.moans in. an. endavaili ct. .Said.casingoopticallyaliencdwith, said.

reectcn for.. viorvinaliebt from Said.. adjacent.

tionl. of. the -.coti.oal oath..bctvtccn said; .Sighting means and saidreflector and being providedwith ncrifrciiecting interiomurfaoca,

y iceportaloledorment the. character-.described comprisingyan elongatedgading, said. Callg. being divdodieenorally longitudnallr thereof to.form.. nrst and... scoondiscotionsn .battery .means and a, lightsouroein Saidlrstsccticnio removable pob u titionccarried .byaid'sccondscotionand, having anapcrtureiormedtherein auxiliary from@ mem:V

ber1 supported by, Sa1d`...partiiion,andtarranecd .to form therevvitit.4an.. elongated.. goidcwar and.. a. chamber.havlosflortionsladiacentsoidapertura.

` anadjlltable Comparisommeniber arranged insaid,;gundam/ay.-l andvaremovablespcoimen holder positioricddnaid ,chamloen. aV rcect or. means.formed-las,,aaunitarr1A partei ,said sframe member for.lsupportingmand.accurately,positioning said re iicctor identical...alianmcntwith, ,adjacent ror-` tionsofcsaid adiustablemomber and. Saidholder, neleasble ,Il lliis caliiodjbysad .frame member for yieldablyholding said reflector inoperative positicnwsighting ,means amend- Wall;cf. said caslng.v optically alignedawithfsaid renector for. vlevvins...light fromsaidedjacent portions and rciieotod br,4 Said rcilectorwheajlluminated by said'light. source. and.. asighting ,channel formedintegrally.,fwidiaidiramo member. and partially enclosingasubstantiaizporticri ohthc optical pathbetwecn.. said sighting., moans.and said, rccctcr being,provided;withnon-renecting` interiorsurfaces...

51. enortableidcviceof, 1thc.character. ,described comprisingan.elongated.oasi-nasaid casing beine divided generally, longitudinally.thereof Y to forza seplrablefli .andsecond sections, battery meansand..a light Sourceinasaidrst section, aiemovaule,4 partitiodcalzriedfbysaicLse-.cond sectionv and havineiaicontralianenturei and apainot endaperturesformcdthcrein.. aopairf ci resilient catches carried ythe..irstsection and ,engaging insaid c nd,acnerturea.fonreleasaloly retainingysaid sections ,in operative. relation, afunitary framememberSllpPQllledfby safidf'partition,fandfbeing;.removabletlicrcvvithhandibeing ,arrangcdto forze with said partition arielongatcdguidcwav Vand acham-- loer.Y having.. portioneadiaccrit said.. central` arcitu1eanadiustable comparison member arranged in saidguidevvayandiarernoilable,specimen holder pos,iilllnerLinv saidhamber, areflector, mountine .Incansformcd asiaeunorxipart .ciaid frame memberefor; Supporting; and..ooourate1y pcsiticm ingisais rcdectoaimoptoal.alignment with adia cent portions otsaidedjiiotelolc,member.andsaid.Iiitary frame mem;

holder, and sighting means in an end wall o f said casing for'viewinglight from said adjacent portions and reflected by said reflector whenilluminated by said light source.' I

6. A portable device of the character described comprising an elongatedcasing, said ycasing being divided generally longitudinally thereof toform separable rst and secondY sections, battery means and a lightsource in said rst section, a removable partition carried by said secondsection and having a central aperture and a pair of end apertures formedtherein, a pair of resilient catches carried by the first section andengaging in said end apertures for releasably retaining said sections inoperative relation, a unitary frame member supported by said partitionand being removable therewith, and being arranged to form with saidpartition an elongated guideway and a chamber having portions adjacentsaid central aperture, an adjustable comparison member arranged in saidguideway and a removable specimen holder positioned in said chamber, areflector, mounting means formed as a unitary p art of said frame memberfor supporting and accurately positioning said reflectorin opticalalignment with adjacent portions of said adjustable member and saidholder, releasable means carried by said frame member and yieldablyholding said reflector in operative position, and sighting means in anend wall vof said casing for viewing light from said adjacent portionsand reflected by said reflector when illuminated by said light source. Y

7. A portable device of the character described comprising an elongatedcasing, said casing being divided generally longitudinally thereof toform separable first and second sections, battery means and a lightsource in said rst section, a removable partition carried by said secondsection and having a central aperture and a pair of end apertures formedtherein, a pair of resil- Y a removable specimen holder positioned insaid chamber, a, rellector, mounting means formed as a unitary part ofsaid frame member for supporting and accurately positioning said reectorin optical alignment with adjacent portions of means in an end wall ofsaid casing optically aligned with said reector for viewing light fromsaid ladjacent portions and reflected by said reector when illuminatedby said light source, and a sighting channel formed integrally with saidframe member and partially enclosing a substantial portion of theoptical path between said sighting means and said reflector and beingprovided with non-reflecting interior surfaces.

8. A portable device of the character described comprising an elongatedcasing, said casing being divided generally longitudinally thereof toform separable first and second sections, battery means and a lightsource in said first section, a removable partition carried by saidsecond section and having a central aperture and a pair of end aperturesformed therein, a pair of resilient catches carried by the flrstsectionand engaging in said end apertures for releasably retaining said secsaidadjustable member and said holder, sightingv tions inoperative relation,a unitary frame mem'- ber supported by said partition and beingremovable therewith, and being arranged to form with said partition anelongated guideway and y a chamber having portions adjacent said centralaperture, an adjustable comparison member arranged in said guideway anda removable specimen holder positioned in said chamber, a reector,mounting means formed as an integral part of said frame member forvsupporting and accurately positioning said reflector in opticalalignment with adjacent portionsof said adjustable member and saidholder, Vreleasable means carried by said frame memberand yieldablyholding said reflector in operative position, sighting means in an endwall of said casing optically aligned with said reiiectorforlviewinglight-from said adjacent portions and reflected by said reilector whenilluminated by said light source, and a sighting channel formedintegrally with said frame member and partially enclosing a substantialportion of the optical path between said sighting means and saidreflector and being-provided with nonreiiecting interior surfaces.

9. A portable device of the character described comprising an elongatedcasing, said casing being divided generally longitudinally thereof toform rst and section s'ections,-battery means and a light source in saidfirst section, a removable partition carried by said second section andhaving an aperture formedtherein, an integral frame member supported bysaid partition and being removable therewith, and being arranged to formtherewith an elongated guideway and a chamber having portions "adjacentsaid aperture, an adjustable comparison member arranged in said guidewayand a removable specimen holder positioned in said chamber, a reflector,means formed as an integral part of saidr frame member for supportingand accurately positioning said reflector in optical alignment withadjacent portions of said-adjustable -member and holder, said partitionhaving formed along one longitudinal side thereof an integral flangeextending away from the plane of said partition and forming an enclosingwall'for said guideway, a carrier for guidingsaid adjustable comparisonmember in said guideway, said carrier having an operating arm secured'thereto and extending outwardly of said flange and through anv elongatedslot in a side wall of said casingso as to form an exposed fingeraccessible to thev operator of the device, and sighting means in .an endwall of said casing for viewing light vfrom saidV adjacent portions andreflected by said reflector when illuminated by said light source.

10. A portable device of the character described comprising an elongatedcasing, said casing being divided generally longitudinally thereof toform rst and second sections, battery means and a light source in saidfirst section, a removable partition carried by said second section andhaving an aperture formed therein, an integral frame member supported bysaid partition and being removable therewith, and being arranged to formtherewith an elongated guideway and a chamber havingvportions adjacentvsaid aperture, an adjustable comparison member arranged in said guidewayand a removable specimen holder positioned in said chamber, a reflector,means formed as an integral part o f said frame member for n supportingand accurately positioning said reflector in optical alignmentl withadjacent portions of said adjustable member and holder, said partitionhaving formed along one longitudinal ngenaccessible to the; operator ofthe device,y

sightingmeansin an endfwall of saidcasing for ,viewing lig-htiromsaidcadjacentportions and -reiiected by vvsaid; reflector whenilluminated. by saidsligh-tlsource, andspring means between `asur-facecf saidfflangeand said carrier for urging said carrier-intof-frictional.slidable engagement ing-being dividedgenerallylongitudinally thereofv -to form iirst and.l second sections,battery-bv meanseandfaflight source-,insaid first section, aremovableapartition, carried byA said. second section and having anaperture. for-medtherein, `an integral frame -member supported bysaidpartition andbei-ngremovable therewith, and being arranged tofformytherewith an elongated guide- Wayl and al chamber having portionsadjacent saidaperturefan adjustable comparison member arrangedrinsaidlguideway and a removable spec-imenholder positioned in-saidchamber, re-

silient armsdn `said Ichamber and Ylongitudinally spaced atoppositesides of said aperturefor yieldably retainingfsaid holder- 4inoperative ,p osition,` a reflector, .-meansformed as an Aintegral`partof said framemember. for supportingand' accurately posi-tioningfsaid-reflector in optical alignment.,withwadjacent portions of saidadjustable Inembrerl andholder,gand sighting meansfin an endWallofsaid`casingwior viewing light `from said -adjacent portions andzre'ected bysaidre- Viiector'- when filluminated by. saidflight source.-

integral frame member-supported by. saidlparti- Y tion and-beingremovabletherevvith, and being arranged `.to form therewith an elongatedguide- Way anda chamber h'avingportions adj acentfsaidapertura-anadjustable comparison member. ar-

rangedfin saidguidewayan'd a-removable speci-- men holder positioned insaid chambery resilient arms-in saidjchamber 'and longitudinally, spacedat.,` opposite sides.- of saidA aperture for yieldably retaining said'holder-infoperativeposition, v arreiiector, Ameans .formed I. as fraunitary rpartof saidframe member vfor supporting and accurately`Dositioning .Y said -reector in .optical alignment-with adjacent..portions Y of said sadj ustable member and holder, releasablemeans carried-by said rframe memberV Afor yieldably holding-saidreflector in` operative position,.and.sighting.means in anend Wall.4 offsaid. casing. -for viewing lightV from said adjacent `portions and Yreflected by-said reflector When ,A illuminated1 by said light source.

V13. A,portable device of. the, characterI described comprising anelongated casingsaid casing being, divided. generally. longitudinallythereof. toV formQiirstyand. second sections, battery means; and alightsource.- in. said 'rst .section, a removablepartition carried, by` saidsecond section and 'having an aperture formed therein, a

lI2 Y unitary, framelmember. supported'byl said 'partition andybeingremovabletherewith, and'being arranged to form therewith .anelongatedguide- Wayand. achamberf'having portions adjacentsaidraperture, ,an adjustable. comparison Vmember arranged lin saidguidevvay and a removable specimen holder .positioned in (said chamber,resilient arms .in said chamber and longitudinally spaced at-oppositefsidesof said aperture for yieldably retaining said hold'erlinoperative position, a reflector, means .formed as afu'n'itary part ofsaid frame member vforsupporting and accurately positioningsaidre'ectorfin optical alignment with adjacentportionstof'.saidadjustablemember and holder, sightingmeans 4in an.endwall ofsaid casing, optically, aligned. With-said reflector for viewinglight.from. said, adjacentv portions and reiiected by saidre'flect'orr whenilluminated by said .lighttsourcef and, a sighting channel formed.integrally With Ysaid frame member; and partially enclosingasubstantialportionof the optical'path between said A sighting means. and saidreflector, said channel. being provided .With non-reflecting interiorsurfaces.

'14.,Apportable deviceV ofV the character describedcomprising'anelongated casing, said casingl being; divided .generally longitudinallythereof to form first and. second4 sections, battery means andailightsfsource infsaidfrst section, a removable.; partition-carried by.said second section andhavingan;aperturejformed therein, a unitary framemember supported by saidjparti- -tionfand --being removable therewith,andY 'being arranged. to form-.therewith an .elongated guide- Way-,andachamber'havingeportions adjacent said aperture,I ,Y an adjustable..comparison Y member arranged f; in.x said gnideway. and a removablespecimen-holder positionediin said chamber, resilient arms: infsaidrohamber.; and-longitudinally. spaced .at oppositesides` of.. said.Vaperture for. yieldably retainingaidlholder; in operative position, areiiector, nmeansiorrnedzas a unitary part of said frame memberVforrsupporting `and accurately po- I sitioning rsaid reileetorfl-in;optical alignment with .adjacent por-tionsof, said adjustable comparisonmember and holden releasablemeans carried by saidframemembenforyieldablyQ holding said reiiectorwinoperative position,sighting means in an end.Wallof.saidlcasingoptically aligned with @saidreflector. for-.viewinglightirom said adjacent :portions-and-reflectedby-said reiiectorv When illuminated said.lightfsource, and .a.sighting `channel :formed:- integrally .with ,said framemembereand,partially` enclosingL a- .substantial portion 55,oi`f-the.-opticalrpath between ,said lvsighting means andisaid. reector, Isaidchannel` being provided Withi `non-rohesting,:interiori surfaces.

15..A. portable. device ofrthe character described comprisingy anelongated` casing divided -.generally longitudinally so` asv Ito form,-separable iirstand secondfsections, battery. means. and a light sourcein' said first-section and va Y.manually .operableswitchconnectedthereto, sighting means in an eend l Wall off said second; section, atrans- 65w verselygdisposed` partition.- detachablyv secured to saidsecondisectionsadjacent. the peripheral edge thereofand-:ai'langedtosubstantially enclose vthe interior-thereoiawhensaid-sections .are separated,

anv adjustableV comparison member: and a speci- 7men Vholdermin .saidsecondrsection, j unitary sup- .portingT means.-carriedr-byfandcooperatingwith `saidfpartition.fonproviding.al longitudinal guide-UWay. tor-.said.comparison-.member and a chamber for said specimenholdcr,;a1reiiector transversely 75 aligned with said chamber and anadjacent portion of said guideway, and accurately formed opposedsurfaces on said unitary supporting means arranged to engage portions ofsaid reilector and xedly support said reflector so as to direct lightfrom said light source and transmitted simultaneously by said comparisonmember and a specimen when positioned in said specimen holder towardsaid sighting means.

16. A portable device of the character described comprising an elongatedcasing divided generally longitudinally so as to form separable rst andsecond sections, battery means and a light source in said first sectionand a manually operable switch connected thereto, sighting means in anend wall of said second section, a transversely disposed partitiondetachably secured to said second section adjacent the peripheral edgethereof and arranged to substantially enclose the interior thereof whensaid sections are separated, an adjustable comparison member and aspecimen holder in said second section, unitary supporting means carriedlby and cooperating with said partition for providing a 1ongitudinalguideway for said comparison member and a chamber for said specimenholder, a re- 25 i'lector transversely aligned with said chamber and anadjacent portion of said guideway, accurately formed opposed surfaces onsaid unitary supporting means arranged to engage portions of saidreector and xedly support said reilector so as to direct light from saidlight source and transmitted simultaneously by said comparison memberand a specimen when positioned in said specimen holder toward saidsighting means, and filtering means of predetermined characteristicscarried by said second section in a position so as to filter the lightbefore same passes to said sighting means. MORDEN G. BROWN. HARRY F.LUNDBERG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,355,960 Due Aug. 15, 19442,396,260 Gradisar et al Mar. 12, 1946

